This invention relates in general to imaging and, more particularly, to a method and apparatus of using a moving camera or fixed sensor array for 3-dimensional scanning of an object.
In many computer applications, it is desirable to have the ability to generate a file describing a three dimensional object. For example, in order to reverse engineer a mechanical part for which drawings are no longer available, it is desirable to be able to efficiently and accurately generate a digital file describing the part. One method is to scan the part with a 3D scanner such as a laser scanning device, generating a digital model therefrom. The models can then be manipulated using computer aided-design/computer aided manufacturing (CAD/CAM) processing techniques to reproduce the desired part. 3D scanners are used in a variety of fields including medical imaging, topography, computer aided-design/computer aided manufacturing (CAD/CAM), architecture, reverse engineering and computer animation/virtual reality.
Early 3D scanners used mechanical probes moving across an object's surface. A mechanical arm connected to the probe moves in accordance with the contours of the surface, and the arm movements are translated into information describing the location of the probe at multiple points. These early digital systems are slow, since they must touch each position on the object at which a measurement reading is taken, and are not suitable for scanning soft objects such as clay. Further, they are not suitable for modeling large 3D spaces or scenes, such as the interior of a room or building.
More recently, optical 3D scanners have become available. 3D scanners of this type project a laser pattern on an object and determine the location of points on the object using triangulation techniques. These systems can be extremely complicated and, therefore, costly. Further, laser systems are limited to a monochromatic light source, limiting their usefulness. Still further, some materials may be opaque or transparent at the frequency of the laser, further limiting their usefulness.